Soap product



Patented Jan. 27, 1942 SOAP PRODUCT Benjamin H. Thurman, Bronxville, N.Y., assi nor to Refining, Inc., Reno, Nev., a corporation of Nevada NoDra'wing. Application December 19, 1938, Serial No. 246,726

7 Claims.

This invention relates to soap products and more particularly toproducts including soap and at least a portion of the minor constituentswhich occur in the residual products resulting from the refining orpartial refining of vegetable oils.

In the alkali refining of vegetable oils, an excess of an alkalirefining reagent over that necessary to combine with the free fattyacids contained in the oil is added to and mixed with the oil. Therefining reagent, which is usually an aqueous solution of causticalkali, such as caustic soda, reacts with the free fatty acids in theoil to produce soap. The alkali also attacks a portion of the neutraloil to produce soap and glycerine. Also the refining reagent reacts withor otherwise causes minor constituents present in the oil, commonlycalled gums and coloring matter, to precipitate or become adsorbed bythe soap. The soap along with the minor constituents are separated fromthe oil either by a gravity settling operation or by centrifugalseparation. Elevated temperatures are usually employed to facilitateseparation. The heavier material separated from the oil is calledsoapstock and includes soap, glycerine, neutral oil, water, uncombinedalkali and the minor constituents referred to. The minor constituentscontain extremely complex chemical compounds, the exact compositions ofmany of which are unknown. It is known that organic matter, is asfollows:

Composition of cottonseed oil Joots Per cent Fatty anhydrides 48.50Glycerine 3.98 Caustic soda (NazO) 3.20 Foreign organic matter 5.90Water 36.00 Coloring matter; 2.42

Soapstock has been utilized to some extent as l a raw material for soapmaking processes. When so used, the soapstock has been subjected to;extensive purification treatments to remove the minor constituents priorto incorporating the remaining soap into soap products. Thus, thesoapstock has been boiled in kettles with additional alkali forsaponifying the entrained neutral oil and the impurities includingglycerine repeatedly washed and salted out in order to produce as puresoap as practicable. Because of its poor detergent and foamingproperties, resultant soap has been employed only in low grade soaps orwashing powders in relatively small percentages and even this use isdecreasing.

Also the fatty acids forming part of the soap in soapstock have beenrecovered and employed in soap making processes by acidulating thesoapstock and distilling off the fatty acids leaving a decomposedinsoluble residue known as pitch having substantially no value and nodetergent properties. The fatty acids recovered and employed as soapmaking materials are substantially free from the minor constituents.Also when employing vegetable oils as soap making bases, they have beencarefully refined to remove and discard the gums and other minorconstituents prior to use in soap making processes. Thus the minorconstituents have been systematically avoided in soap products.

The soapstock recovered from a refining process containing such minorconstituents as well as large amounts of water is susceptible to rapidfermentation and decomposition. It has, therefore, been impossible tostore or ship soapstock without putrification unless it had beenpurified. Any attempt to employ even a partly fermented soapstock in asoap product results in an evil smelling and highly discolored product.

In accordance with the present invention, I have discovered that theminor constituents of soapstock perform extremely valuable functions insoap products both for detergent and other uses. I have found that theseminorconstituents have extremely valuable detergent enhancing propertiesand not only give to the soap product improved foaming and emulsifyingproperties but also provide excellent wetting or surface tensionreducing and water softening properties. By water'softening properties Imean the capability of preventing the deposition of insoluble alkalineearth compounds and not the precipitation and separation from the waterof such compounds. I have further discovered that fermentation andputrification of products including the same can be prevented.

It is, therefore, an object of the invention to provide a new productcontaining the detergent enhancing constituents present in the originaloil or contained in the material separated from vegetable oils duringrefining or semi-refining thereof.

Another object of the invention is to provide an improved soap productcontaining substantial quantities of the minor constituents of vegetableoil which have detergent enhancing properties.

Another object of the invention is to provide an improved process ofincorporating soapstock from the alkali refining of vegetable oils intosoap products so as to prevent decomposition of the minor constituentsof said soapstock.

Another object of the invention is to provide a new water softening andcleaning product containing the detergent enhancing constituents presentin the residue from the refining or semirefining of vegetable oils.

A further object of the invention is to provide a new soap productcapable of being used as a wetting agent or as a foaming or flotationagent.

The products of the present invention have been found to have particularutility in cleaning compositions suitable for spray cleaning devices.Such devices usually include a heating device, such as a heating coil,through which a solution of the cleaning composition is pumped, heatedto a high temperature in the coil and thereafter sprayed upon a surfacefor removing greasy or tarry deposits thereupon. These devices areemployed, for example, in cleaning automobile frames and motors, andprovide a severe test of the stability and detergent properties of acleaning composition.

Solutions of cleaning compositions employed in such devices must havegood wetting, rinsing and emulsifying properties in order to remove thedeposits referred to and leave a clean surface. Also any precipitate ofinsoluble soaps or other insoluble compounds due to the employment ofhard water in the cleaning solution not only sticks to the surfaces tobe cleaned but forms deposits upon the walls of the heating coil. Thesedeposits form large amounts of scale interiering with heat transferenceand eventually plug the heating coil. Cleaning compounds employed withsuch devices have, heretofore, included expensive alkali metal soaps tosecure sufficient cleaning action, for example, linseed oil sodium andpotassium soaps and also have included substantial amounts of expensivewater softening chemicals, for example, sodium hexameta phosphate orsodium pyro phosphate. The water softening chemicals were employed toprevent the formation of insoluble soaps or other insoluble compounds inthe heating coil by the reactions between the soaps or the alkalies alsoemployed in such compounds and the magnesium or calcium salts present inhard waters.

In accordance with the present invention, I have found that soapstockproduced by the alkali refining of crude vegetable oils originallycontaining the detergent enhancing constituents above referred to, forexample, cottonseed oil, corn oil, soya bean oil, linseed oil, etc., canbe employed in such cleaning compositions instead of expensive soaps,such as, linseed oil soap, and that expensive water softening chemicalsare rendered unnecessary. The minor constituents in the soapstockapparently render even such inthe soapstock or ferior soaps ascottonseed oil soap capable of producing large amounts of stable foam aswell as giving the soap excellent surface tension reducing and watersoftening properties.

The exact explanation of why the detergent enhancing constituentsprevent the precipitation of insoluble alkaline earth metal compoundswhen hard water is used in cleaning devices, is not known to applicant.Alkali metal soaps are present for reaction with the alkaline earthmetal salts, such as calcium or magnesium salts and in this respect thepresent product is different from such surface tension reducing agentsas sulphated fatty acid alcohols, which form no insoluble products withhard water. Such suiphated alcohols have very little cleaning power andalso do not prevent the deposition of insoluble soap if alkali metalsoaps are present. It is believed that the phosphatides, phytinphosphorus compounds'or other of the minor constituents either have theproperty of retaining the insoluble soaps or other insoluble compoundsin suspension or that they prevent the formation of such insolublecompounds. As the soap, including the minor constituents, has effectiveemulsifying or suspending properties, as well as being a good foamingagent forming large quantities of stable foam, it is probable that theformer explanation is correct. Linseed oil soap has been employedbecause of its high solubility resulting in good rinsing properties, butsuch linseed oil soap does not form the stable foam necessary foreffective suspension of the substances to be removed. The minorconstituents of the present products not only increase the solubility orsuspensibility of normally dimcultly soluble soaps but also cause suchsoaps to produce large quantities of stable form. It is believed thatthe phosphatides, at least a part of which are amphoteric anddispersable in both oil and water, are responsible for the wetting orsurface tension reducing properties of the product but applicant doesnot wish to be bound by any precise theories of operation.

The excellent detergent properties of the composition of the presentinvention, particularly when employed in spray cleaning devices, areapparently due, in part, to the formation of substantial quantities ofammonia or amines or both, which compounds are known to have gooddetergent properties. The composition is subjected to elevatedtemperatures and pressures in such spray cleaning devices and it isbelieved that proteinaeeous material is decomposed so as to liberateammonia and amines in active form. The minor constituents of thesoapstock, therefore, constitute an inexpensive source of such detergentagents.

The various properties of the detergent enhancing constituents of thepresent invention persist even in combination with large quantities ofvarious alkali materials commonly used in cleaning compositions. Thusthe soapstock containing such constituents may be mixed with suchalkalies as trisodium phosphate, sodium carbonate, caustic soda orsodium meta silicate. When mixed with one or more of these substances,for example, sodium carbonate or caustic soda having no water ofcrystallization or only small amounts thereof, the alkali will combinewith the water in the soapstock to produce a dry mixture which is stableagainst fermentation or putrification. softening materials, such assodium pyrophosphate or sodium hexa meta phosphate are nec- As statedbefore, no water essary. As typical of several formulas which have beensuccessfully employed in spray cleaning devices in admixture with watercontaining substantial amounts of calcium and magnesium salts, thefollowing is given:

Example I Per cent Corn oil soapstock (H20 40%) (8.4% dry basis) 14.50Trisodium phosphate 11.50 'Soda ash (NazCoz) 41.9

Caustic soda (NaOH) 9.27 Meta-silicate of soda 22.93

Calculated water 21%.

' Example II Per cent Soya bean oil soapstock 25.00 Trisodium phosphate8.3 Soda ash 49.8 Caustic soda 8.3 Sodium metasilicate 8.6

' 100.00 Example III Per cent Corn oil soapstock 7.77 Trisodiumphosphate 12.08 Soda ash 45.15 Caustic soda 10.00 Sodium metasilicate25.00

100.00 Example IV Per cent Cottonseed oil soapstock 80 Soda ash 20 Itwill be noted that the proportions of the alkalies admixed with thesoapstock can be varied widely. It will further be noted that lessexpensive alkalies, such as soda ash and caustic soda, sodiummetasilicate, etc., can be employed or that more expensive alkalies, astrisodium phosphate, can be omitted. By mixing wholly or partlydehydrated alkalies in powdered form with the soapstock in the conditionit is separated from the oil in refining processes, a stable powderedmaterial is produced even though the product may contain substantialamounts of water. In preparing the composition, it is possible to mixone alkali, for example, soda ash or caustic soda with the soapstock asit comes from the refinery in which event a product stable againstdecomposition is produced. which product can be shipped andstored. Oneor more other alkalie can be admixed therewith at a later time ifdesired. For example, dry soda ash containing not more than 2 moleculesof water per molecule of NazCOa is commerciallyavailable and willcombine with the water of the soapstock to form NazCOc--10HzO. If suchprocedure is not practicable the soapstock may be rendered stable bydrying the same, for example, in accordance with the processes disclosedin my copending application,'Seria1 No. 180,621, filed December 18,1937, or the soapstock may be filmed upon a heated roll to dry the sameand then scraped from the roll in dried condition. As long as the driedsoapstock is maintained in relatively dry condition it is stable againstfermentation or decomposition and can be stored or shipped prior toadmixingthe alkalies therewith.

Also fermentation and decomposition of the soapstock can be prevented bymixing therewith a fermentation retarding agent, for example, es-

sential oils such as oil of cassia, which will effectively prevent thegrowth of fermentation bacteria when added in as small amounts as 1Other fermentation retarding agents which can be employed are phenol,cresol, pine oil, alcohol, benzol, toluene or gasoline in amountsranging from 0.5 to 5% depending upon the particular soapstock or agentemployed. Phenolor cresol are particularly desirable as they react withalkalie to form products having good detergent and solubilizingproperties.

In alternative oil refining procedures, at least a portion of the gumsare removed from the oil prior to complete refining by so-called degumming -or semi-refining processes. The gums recovered, to a large extent.contain the detergent enhancing constituents. The recovery of theseconstituents can be effected by semi-refining, for example, with analkali such as trisodium phosphate so as to neutralize only aportion ofthe free fatty acids or by employment of water or acid reagents, forexample, boric acid, phosphoric acid or hydrogen peroxide. Certain ofthe preserving reagents, such as alcohol, can be added with thedegumming or refining reagents to obtain an even distribution in' thesoapstock or minor constituents. The boric acid, when employed as adegumming agent, is also an effective preserving agent. The gums orminor constituents can also be stabilized against fermentation orputrification by drying the same or admixing them withdry alkali or withthe fermentation retarding agents referred to with respect to soapstock.These gums or minor constituents may be mixed with ordinary sodium orpotassium soaps made from animal or vegetable oils or fats to form theequivalent of the soapstock resulting from the alkali refining of crudeoils containing the minor constituents and employed in the compositionof the present invention. Alternatively, the minor constituents from apartial refining or degumming operation may be mixed with alkalieswithout the addition of soap. Certain of these constituents contain fatty acids which will result in the formation of soaps when heated withsuflicient alkalies. The sodium soap in such composition may be thesoapstock recovered from the alkali refining of the degummed orsemi-refined oil. Such soapstock contains soap, glycerine, neutral oil,uncombined alkali, water, and any of the detergent enhancing minorconstituents which were not removed during the degumming process. It hasat least in part the properties of the ordinary soapstock containingallof the minor constituents. It may, therefore, beemployed alone or withadditional minor constituents from degumming or semi-refining processesin the product of the present invention.

The neutral oil in the soapstock from refining processes is notdetrimental for certain uses. For example, in the spray cleaning devicesre- 'ferred to, the excess alkali of the cleaning com-' positionsemployed, combines with the neutral oil to form soap during the passageof the solution through the heating device so that nosubstantial amountof oil is present in the spray.

Since the soapstock from continuous refining processes, for example,those disclosed in Patents Nos. 2,100,274 and 2,100,275, grantedNovember 23, 1937, contains less neutral oil, because of more eflicientseparation from the oil, they are with the present invention.-

In employing the soap product of the present invention containing largeamounts of alkalies in spray cleaning devices, the preferred operationis to make up a relatively concentrated solution of the soap product andthen mix a small metered stream of the resulting solution with a flowingstream of water, which stream is then heated to form the cleaning spray.For example, a 10% solution of the soap product may be pumped into astream of water to produce a final solution containing about 4% of thesoap product. In many cases, the soap incorporated into solutions of 10%or higher concentrations, grain out or produce an emulsion so that auniform proportioned mixture cannot be pumped. I have found that a smallproportion of a liquid volatile soap solvent such as isopropyl alcohol,which is miscible with water, avoids this difficulty. For example, about2% of isopropyl alcohol admixed with the 10% solution above referred towill make the entire soap product soluble so as to produce a clear andthin solution which is easily pumpable. Larger proportions of solventwill be employed with more concentrated solutions and smallerproportions with less concentrated solutions. The solvent is preferablyadmixed with the soap product and sold as an article of commerce so thatthe relatively concentrated solution referred to can be made up bymerely adding the requisite amount of water, but may be added at thetime the relatively concentrated solution is prepared. The solvent alsoperforms a valuable detergent action in softening or dissolving depositsto be removed and enabling them to be removed by the spray. Whileisopropyl alcohol has been given as the preferred material, other soapsolvents which are miscible with water such as ethyl alcohol, butylalcohol, cresol-cresylic acids, etc. can be employed. The cresol orcresylic acids are particularly valuable as they react with the alkalito form detergent compounds and also prevent decomposition of organiccompounds in the composition and the formation of ammonia or aminesuntil the composition is subjected to elevated temperatures in a spraycleaning device.

While the invention has been described above particularly with relationto compositions suitable for use in spray cleaning devices, thestabilized product can also be employed alone or in combination withother ingredients for various other purposes. The powdered materialresulting from mixing alkalies, such as tri-sodium phosphate, soda ashor caustic soda, with the soapstock makes an extremely efiicient washingpowder for uses other than spray cleaning. A

- product containing the minor ingredients referred to is alsoparticularly effective for employment in insecticide sprays along.withsuitable chemicals. The wetting and emulsifying properties of thecomposition-give the spray excellent covering properties and retain thechemicals, even in powdered form, in even suspension in the spray larlyuseful with such compounds as chromium solution. The composition isparticu-' salts which tend to precipitate insoluble chromium compounds.Also, the surface tension reducing and foaming properties thereof renderthe product especially suitable for flotation operations, such as oreseparation processes particularly where hard water must be employed. Theproduct may be employed alone or. with other flotation agents and incertain of such processes the presence of unsaponified oil is desirable.It has also been found that the minor constituents of the product areeffective agents in solvent spraying processes for retarding evaporationof the solvent. Thus, organic solvents are frequently sprayed uponsurfaces to remove accumulations of grease or tars, or as paintremovers. Large amounts of the solvents are lost by evaporation in thespray before contact with the surface and also considerable evaporationfrom the surface takes place befor the solvents effectively dissolve theaccumulations to be removed. Substantially all of the minor constituentsare soluble in many of such organic solvents and at least portionsthereof are soluble in most organic solvents. The portion whichdissolves in the solvents has been found to decrease the rate ofevaporation of the solvents so as to effect substantial savings in theamount of solvent necessary to cover or dissolve accumulations upon asurface from which they are to be removed. Thus, the compositions of thepresent invention find general utility in soap and other products.

This application is a continuation-in-part of my copending applicationSerial No. 225,063, filed August 15, 1938. A

While I have disclosed the preferred embodiments of my invention, it isunderstood that the invention is not limited to the details disclosedbut may be varied within the scope of the following claims.

I claim:

1. As a product of manufacture, a composition of matter which comprises,alkali metal soap, a substantial amount of gums recovered from crudevegetable oils, a substantial amount of at least one alkali metalcompound having an alakline reaction in addition to any alkali presentin said gums when recovered from said crude oil, and an organic soapsolventmiscible with water, said composition being stable againstfermentation.

2. As a product of manufacture, a composition of matter which comprises,alkali metal soap, a substantial amount of gums recovered from crudevegetable oils, and a substantial amount of at least one alkali metalcompound having an alkaline reaction in addition to any alkali presentin said gums when recovered from said crude oil, said composition beingsufficiently free from water to be stable against fermentation, and anorganic soap solvent miscible with water admixed with said composition.

3. As a product of manufacture, a composition of matter which comprises,alkali metal .soap, a substantial amount of gums recovered from crudevegetable oils, a substantialamount of at least one' alkali metalcompound having an alkaline reaction in in said gums when recovered fromsaid crude oil, and an organic soap solvent miscible with water, saidcomposition containing a fermentation inhibiting agent for said gums insufficient amount to render said composition stable againstfermentation.

4. As a product of manufacture, a composition of matter which comprises,soap stock from the alkali refining of crude vegetabl oils includingaddition to any alkali presentsoap, gums, an alkali, said compositionalso containing a substantial amount of at least one alkali metalcompound having an alkaline reaction in addition to any alkali presentin said soap stock, and sufllcient organic soap solvent miscible withwater to'prevent graining out of soap when said product is in an aqueoussolution of the order of concentration, said composition containingsubstantially all of said gums in said soap stock and being stableagainst fermentation.

5. As a product of manufacture, a composition of matter which comprises,soap stock from the alkali refining of crude vegetable oils includingsoap, gums, and an alkali, said composition also containing asubstantial amount of at least one alkali metal compound having analkaline reaction in addition to any alkali present in said soap stock,said composition containing substantially all of said gums in said soapstock and being sufiiciently free of water to be stable againstfermentation, and suflicient organic soap solvent miscible with wateradmixed with said composition to prevent graining out of soap when saidproduct is incorporated in an aqueous solution of the order of 10%concentration.

6. As a product of manufacture, a. composition of matter whichcomprises, soap stock from the alkali refining of crude vegetable oilsincluding soap, gums, an alkali, said composition also containing asubstantial amount of at least one alk ali metal compound having analkaline reaction in addition to any alkali present in said soapfiningof crude vegetable oils including water,

soap, gums and an alkali, said composition also containing a substantialamount of soda ash in addition to any alkali present in said soap stockand being sufliciently free of water to be stable against fermentation,said composition containing substantially all of said gums in said soapstock and said gums being present in suflicient amount to prevent thedeposition of insoluble compounds when said composition ismixed withhard water and heated and to substantially increase the foaming, rinsingand emulsifying properties of the soap, and sufficient organic soapsolvent miscible with water admixed with said composition to preventgraining out of soap when said product is incorporated in an aqueoussolution of the order of 10% concentration.

BENJAMIN H. THURMAN.

